Abstract: A flash memory device is provided. The flash memory device includes a memory cell array and a pre-charge unit. The pre-charge unit, coupled to a plurality of bit lines corresponding with the memory cell array, pre-charges the bit lines to a predetermined voltage during a pre-charge stage. The pre-charge unit includes a voltage stabilizing unit to provide a constant current to the bit lines. Due to the voltage stabilizing unit, in a programming process, the voltage applied to the bit lines which are not related with programming may not drop as a result of current leakage. Therefore, the memory cells except the memory cell to be programmed are kept in cut off state, without a current passing. As a result, interference with the memory cells which are not to be programmed may be effectively avoided and the accuracy of programming may be improved.
Abstract: A household appliance configured to communicate with a second household appliance, a network of household appliances that can communication with each other, and method of controlling an operation of a primary function unit of a first household appliance based on one of a priority scheme and synchronized duty cycles of the first household appliance and the second household appliance, wherein the first household appliance is configured to communicate with the second household appliance. The household appliance includes a primary function unit, a controller that controls an operation of the primary function unit, a two-way communication module that transmits and receives signals between the controller and the second household appliance.
Type:
Grant
Filed:
June 16, 2011
Date of Patent:
January 27, 2015
Assignee:
BSH Home Appliances Corporation
Inventors:
Michael Gerdes, Bruce Simmons, Paul Wintrode
Abstract: Embodiments of apparatus and methods having a memory device can include a line to exchange information with a string of memory cells and a transistor coupled between the string of memory cells and the line. Such a memory device can also include a module configured to couple a gate of the transistor to a node during a first time interval of a memory operation and decouple the gate from the node during a second time interval of the memory operation. Additional apparatus and methods are described.
Abstract: A semiconductor device includes a memory block coupled to word lines and configured to a memory cell including a floating gate, an inter-poly dielectric and a control gate and a peripheral circuit configured to perform an erase loop operation, a program loop operation an electron injection operation of the memory cell, the electron injection operation trapping electrons in the inter-poly dielectric.
Abstract: A nonvolatile memory device comprises cell strings formed in a direction substantially perpendicular to a substrate and is configured to select memory cells in units corresponding to a string selection line. The device selects a page to be programmed among pages sharing a common word line, determines a level of a program voltage to be provided to the selected page according to a location of a string selection line corresponding to the selected page, and writes data in the selected page using the determined level of the program voltage.
Abstract: Semiconductor memory cells, array and methods of operating are disclosed. In one instance, a memory cell includes a bi-stable floating body transistor and an access device; wherein the bi-stable floating body transistor and the access device are electrically connected in series.
Type:
Application
Filed:
February 15, 2013
Publication date:
January 22, 2015
Inventors:
Yuniarto Widjaja, Jin-Woo Han, Benjamin S. Louie
Abstract: Apparatuses and methods for measuring an electrical characteristic of a model signal line and providing measurement information based at least in part on the measurement of the electrical characteristic. An example apparatus includes a signal line model including a model signal line configured to model electrical characteristics of a signal line. The apparatus further includes a measurement circuit coupled to the signal line model and configured to measure the electrical characteristic of the model signal line responsive to an input signal provided to the model signal line. The measurement circuit is further configured to provide measurement information based at least in part on the measurement to set a signal applied to the signal line.
Abstract: Methods of maintaining a state of a memory cell without interrupting access to the memory cell are provided, including applying a back bias to the cell to offset charge leakage out of a floating body of the cell, wherein a charge level of the floating body indicates a state of the memory cell; and accessing the cell.
Abstract: A semiconductor memory device includes a memory block including memory strings coupled to and disposed between bit lines and a common source line, and a peripheral circuit configured to perform a read operation of memory cells included in selected memory strings of the memory strings and increase channel potential of unselected memory strings in the read operation.
Abstract: The voltage of a selected word line is increased beyond the voltage to which a respective string driver transistor is capable of driving the word line by capacitively coupling a voltage to the selected word line from adjacent word lines. The voltage is capacitively coupled to the selected word line by increasing the voltages of the adjacent word lines after a programming voltage has been applied to a string driver transistor for the selected word line and after a string driver voltage has been applied to the gates of all of the string driver transistors in an array.
Type:
Grant
Filed:
March 24, 2014
Date of Patent:
January 20, 2015
Assignee:
Micron Technology, Inc.
Inventors:
Violante Moschiano, Giovanni Santin, Ercole Di Iorio
Abstract: An overclocking process for a data storage device using a flash memory. A controller for the flash memory tests the flash memory using test clocks with various frequencies to determine at least one clock signal suitable to the flash memory. The clock candidates suitable to the flash memory are selected from the test clocks. The flash memory is operated in a variable-frequency manner by which the flash memory is switched between the clock candidates, such that electromagnetic interference is spread over different bands.
Abstract: Disclosed are a semiconductor memory device and an operating method thereof. The semiconductor memory device includes a memory cell block including a plurality of memory cells, a voltage providing unit suitable for providing a pass voltage or a read voltage to word lines coupled with the memory cells and a control circuit suitable for controlling the voltage providing unit to adjust a pass voltage applied to the memory cells disposed at one side of a selected memory cell and a pass voltage applied to the memory cells disposed at the other side of the selected memory cell based on an address of a word line of the selected memory cell among the memory cells during a read operation or a verification operation.
Abstract: An integrated circuit device. The device includes an address input(s) configured to receive address information from an address stream from an address command bus coupled to a host controller and an address output(s) configured to drive address information, and is coupled to a plurality of memory (DRAM) devices provided on a DIMM. The device has an address match table comprising a non-volatile memory device configured to store at least a revised address corresponding to a spare memory location and a bad address of at least one of the plurality of memory (DRAM) devices. The device has a control module configured to process and determine whether each address matches with a stored address in the address match table to identify the bad address and configured to replace the bad address with the revised address of the spare memory location.
Type:
Application
Filed:
August 29, 2014
Publication date:
January 15, 2015
Inventors:
Hamid Reza RATEGH, David T. WANG, Lawrence TSE
Abstract: A memory array structure is provided. The memory array structure comprises a ring-shaped electrical pattern comprising a plurality of word lines, an array area comprising a first array, a second array and a plurality of bit lines, and a contact area comprising a plurality of contact points. The first array comprises one part of the word lines, and a first ground select line and a first string select line disposed on both sides of the word lines. The second array comprises another part of the word lines, and a second ground select line and a second string select line disposed on both sides of the word lines. The bit lines are disposed on the first array and the second array, and cross both of the first array and the second array. The word lines electrically contact with an external circuit through the contact points.
Abstract: In aspects of the invention, an auxiliary memory circuit includes a shift register wherein a plurality of flip-flops are cascade-connected and a plurality of inversion circuits that invert and output outputs of each D flip-flop. A main memory circuit includes a switch, which acts in accordance with a signal from the auxiliary memory circuit, and an EPROM connected in series to the switch and driven by a writing voltage. A variable resistance circuit includes a switch, which acts in accordance with a signal from the auxiliary memory circuit, and a resistor connected in series to the switch. With aspects of the invention, it is possible for terminals of the writing voltage and a writing voltage to be commonized. Also, it is possible to provide a low-cost semiconductor physical quantity sensor device that can carry out electrical trimming with the voltage when writing into the EPROM kept constant.
Abstract: To provide a memory element where a desired potential can be stored as data without an increase in the number of power source potentials. The memory element stores data in a node which is brought into a floating state by turning off a transistor a channel of which is formed in an oxide semiconductor layer. The potential of a gate of the transistor can be increased by capacitive coupling between the gate and a source of the transistor. With the structure, a desired potential can be stored as data without an increase in the number of power source potentials.
Type:
Grant
Filed:
July 12, 2013
Date of Patent:
January 13, 2015
Assignee:
Semiconductor Energy Laboratory Co., Ltd.
Abstract: A nonvolatile memory device and a method of operating the same are provided. The method includes performing a plurality of program operations on a plurality of memory cells each to be programmed to one of a plurality of program states, performing a program-verify operation on programmed memory cells associated with each of the plurality of program states, the program-verify operation comprises, selecting one of the plurality of offsets based on a noise level of a common source line associated with a programmed memory cell, using the selected offset to select one of a first verify voltage and a second verify voltage higher than the first verify voltage, and verifying a program state of the programmed memory cell using the first verify voltage and the second verify voltage.
Abstract: A clock mode configuration circuit for a memory device is described. A memory system includes any number of memory devices serially connected to each other, where each memory device receives a clock signal. The clock signal can be provided either in parallel to all the memory devices or serially from memory device to memory device through a common clock input. The clock mode configuration circuit in each memory device is set to a parallel mode for receiving the parallel clock signal, and to a serial mode for receiving a source synchronous clock signal from a prior memory device. Depending on the set operating mode, the data input circuits will be configured for the corresponding data signal format, and the corresponding clock input circuits will be either enabled or disabled. The parallel mode and the serial mode is set by sensing a voltage level of a reference voltage provided to each memory device.
Abstract: A nonvolatile memory device performs a read operation comprising first and second intervals. In the first interval the device applies a turn-on voltage to string selection lines and ground selection lines connected to the string selection transistors and the ground selection transistors, respectively. In the second interval, the device applies a turn-off voltage to unselected string selection lines and unselected ground selection lines while continuing to apply the turn-on voltage to a selected string selection line and a selected ground selection line. In both the first and second intervals, the device applies a first read voltage to a selected wordline connected to memory cells to be read by the read operation and applying a second read voltage to unselected wordlines among connected to memory cells not to be read by the read operation.
Abstract: A source of charge carriers in thin film transistor-based memory devices is provided for a memory. The source of charge carriers can include a diode having a first and second terminal. A NAND string coupled on a first end via a first switch to a bit line, is coupled on a second end via a second switch to the first terminal of the diode. Separately drivable first and second supply lines are coupled to the first and second terminals, respectively of the diode. Circuitry is included that is coupled to the first and second supply lines, that is configured to bias the first and second supply lines with different bias conditions depending on the mode of operation, including forward bias conditions and reverse bias conditions.
Abstract: A device for use with non-volatile memory, includes a first transistor of a first channel type coupled between first and second nodes, including a control gate supplied with a first control signal having a first phase, a second transistor of a second channel type different from the first channel type including a first terminal coupled to the first node, a second terminal coupled to a third node, a back gate coupled to the first terminal thereof, and a control gate supplied with a second control signal having a second phase substantially opposite to the first phase, a third transistor of the second channel type including a first terminal coupled to the second node, a second terminal coupled to the third node, a back gate coupled to the first terminal thereof, and a control gate supplied with the second control signal, and a protection circuit coupled between the first and second node.
Abstract: According to one embodiment, a memory system includes a nonvolatile semiconductor memory device, a voltage generation unit and a control unit. The nonvolatile semiconductor memory device includes a memory cell array having a plurality of blocks each including a plurality of memory cells, and a voltage generation unit configured to change a read level of the memory cell. The control unit controls write, read, and erase of the nonvolatile semiconductor memory device. The control unit changes the read level between a start of use of the nonvolatile semiconductor memory device and a timing after an elapse of a time.
Abstract: According to one embodiment, a control circuit of a memory cell array is configured to write data to a memory cell array by applying a first write pass voltage, which is lower than the program voltage, to a first group of nonselective word lines adjacent to a selective word line. The control circuit is further configured to apply a second write pass voltage, which is higher than the first write pass voltage, to a second group of second nonselective word lines, the second group not including the word lines of the first group.
Abstract: Techniques are described herein for detecting and recovering over-erased memory cells in a flash memory device. In one embodiment, a flash memory device is described including a memory array including a plurality of blocks of memory cells. The device also includes a controller to perform a leakage-suppression process. The leakage-suppression process includes determining that a given block of memory cells includes one or more over-erased memory cells. Upon the determination, the leakage-suppression process also includes performing a soft program operation to increase the threshold voltage of the over-erased memory cells in the given block.
Abstract: A nonvolatile memory device includes a voltage supply controller (VSC) detecting a level of a power supply voltage and generating a first internal voltage in response thereto. The VSC provides the first internal voltage at a level equal to an external high voltage when a power supply voltage is normally supplied, but provides the first internal voltage at a level lower than the external high voltage when a power supply voltage is abnormally supplied.
Abstract: Provided is a programming method of a nonvolatile memory device. The nonvolatile memory device includes a substrate and a plurality of memory cells which are stacked in the direction perpendicular to the substrate.
Abstract: The semiconductor memory device includes a memory cell block including a plurality of memory cells, a peripheral circuit section configured to perform an erase loop including a supply operation supplying an erase voltage and an erase verification operation to erase data stored in the memory cells, a fail bit counter configured to count the number of memory cells not erased in an erase operation among the memory cells to generate a count signal based on a fail count corresponding to a counting result in the erase verification operation, and a controller configured to control the peripheral circuit section to set a new erase voltage by increasing an erase voltage, used in a previous erase loop, by a first step voltage or decreasing the erase voltage by a second step voltage based on the fail count, and perform the erase loop using the new erase voltage.
Abstract: A nonvolatile semiconductor memory device includes a plurality of nonvolatile memory cells formed on a semiconductor substrate, each memory cell including source and drain regions separately formed on a surface portion of the substrate, buried insulating films formed in portions of the substrate that lie under the source and drain regions and each having a dielectric constant smaller than that of the substrate, a tunnel insulating film formed on a channel region formed between the source and drain regions, a charge storage layer formed of a dielectric body on the tunnel insulating film, a block insulating film formed on the charge storage layer, and a control gate electrode formed on the block insulating film.
Abstract: A non-volatile memory device has a charge pump for providing a programming current and an array of non-volatile memory cells. Each memory cell of the array is programmed by the programming current from the charge pump. The array of non-volatile memory cells is partitioned into a plurality of units, with each unit comprising a plurality of memory cells. An indicator memory cell is associated with each unit of non-volatile memory cells. A programming circuit programs the memory cells of each unit using the programming current, when fifty percent or less of the memory cells of each unit is to be programmed, and programs the inverse of the memory cells of each unit and the indicator memory cell associated with each unit, using the programming current, when more than fifty percent of the memory cells of each unit is to be programmed.
Type:
Application
Filed:
August 1, 2014
Publication date:
January 1, 2015
Inventors:
Hieu Van Tran, Hung Quoc Nguyen, Anh Ly, Thuan Vu
Abstract: Provided is a semiconductor memory circuit including an oxide semiconductor insulated gate FET enabling advanced performance without being affected by a variation in threshold voltage.
Abstract: A method of reading a nonvolatile memory device including: applying a read voltage to a selected wordline of the nonvolatile memory device; applying a read pass voltage to unselected wordlines of the nonvolatile memory device; sensing a state of a memory cell connected to the selected wordline; and applying the read pass voltage to the selected wordline after the sensing.
Type:
Application
Filed:
April 1, 2014
Publication date:
January 1, 2015
Inventors:
Sang-Wan Nam, Kitae Park, Hyun-Wook Park, Jae-Kyun Rhee
Abstract: A semiconductor memory device is provided. The semiconductor memory device includes a memory cell array including cell strings coupled between bit lines and a common source line, each of the cell strings comprising a plurality of memory cells stacked above a substrate. The semiconductor memory device also includes a peripheral circuit configured to supply a negative voltage to one or more word lines coupled to the cell strings and supply a positive voltage to the common source line, wherein the peripheral circuit supplies the positive voltage and the negative voltage before a program operation is performed.
Abstract: A semiconductor device includes cell strings that each include a plurality of memory cells, a page buffer having latches coupled to bit lines and precharge the bit lines in response to page buffer control signals, a page buffer control circuit configured to generate the page buffer control signals using a high voltage source, and a controller configured to generate control signals for controlling the page buffer control circuit.
Type:
Grant
Filed:
June 8, 2012
Date of Patent:
December 30, 2014
Assignee:
SK Hynix Inc.
Inventors:
Kwang Ho Baek, Jin Su Park, Chang Won Yang
Abstract: A semiconductor memory device includes a memory cell array including first memory cells and second memory cells connected to at least one word line, a circuit group configured to perform a pre-program operation on the first memory cells using a target voltage and a main program operation on the first memory cells and the second memory cells using a final target voltage, and a control circuit configured to set the target voltage depending on variations in threshold voltages of the first memory cells caused by the main program operation of the second memory cells.
Abstract: An one-transistor-one-bit (1T1b) Flash-based EEPROM cell is provided along with improved key operation schemes including applying a negative word line voltage and a reduced bit line voltage for perform erase operation, which drastically reduces the high voltage stress on each cell for enhancing the Program/Erase cycles while reducing cell size. An array made by the 1T1b Flash-based EEPROM cells can be operated with Half-page or Full-page divided programming and pre-charging period for each program cycle. Utilizing PGM buffer made of Vdd devices in the cell array further save silicon area. Additionally, a two-transistor-two-bit (2T2b) EEPROM cell derived from the 1T1b cell is disclosed with additional cell size reduction but with the operation of program and erase the same as that for the 1T1b cells with benefits of no process change but much enhanced storage density, superior Program/Erase endurance cycle, and capability for operating in high temperature environment.
Abstract: A nonvolatile memory device is provided. The device may include a plurality of cell strings that are configured to share a bit line, word lines, and selection lines. Each of the cell strings may include a plurality of memory cells connected in series to each other and a string selection device controlling connections between the memory cells and the bit line, and the string selection device may include a first string selection element with a first threshold voltage and a second string selection element connected in series to the first string selection element and having a second threshold voltage different from the first threshold voltage. At least one of the first and second string selection elements may include a plurality of switching elements connected in series to each other.
Abstract: Provided is a programming method of a nonvolatile memory device which includes a plurality of strings each including a source select transistor, a plurality of memory cells, and a drain select transistor which are connected in series between a common source line and a bit line. The programming method includes: applying a first voltage to the common source line during a first period in which a channel of a plurality of memory cells of an unselected string is floated; and applying a second voltage increased more than the first in voltage to the common source line during a second period in which a selected memory cell is programmed, when a selected word line belongs to a word line group adjacent to the common source line.
Abstract: According to example embodiments of inventive concepts, a nonvolatile memory device includes a memory cell array including a plurality of memory cells; a word line driver configured to at least one of select and unselect a plurality of word lines connected with the plurality of memory cells, respectively, and to supply voltages to the plurality of word lines; and a read/write circuit configured to apply bias voltages to a plurality of bit lines connected with the plurality of memory cells. The read/write circuit may be configured to adjust levels of the bias voltages applied to the plurality of bit lines according to location of a selected word line among the plurality of word lines.
Abstract: A method is provided for operating a memory system. The method includes reading nonvolatile memory cells using a first soft read voltage, a voltage level difference between the first soft read voltage and a first hard read voltage being indicated by a first voltage value; and reading the nonvolatile memory cells using a second soft read voltage paired with the first soft read voltage, a voltage level difference between the second soft read voltage and the first hard read voltage being indicated by a second voltage value. The second voltage value is different than the first voltage value. Also, a difference between the first voltage value and the second voltage value corresponds to the degree of asymmetry of adjacent threshold voltage distributions among multiple threshold voltage distributions set for the nonvolatile memory cells of the memory system.
Type:
Grant
Filed:
October 10, 2013
Date of Patent:
December 30, 2014
Assignee:
Samsung Electronics Co., Ltd.
Inventors:
Dae-seok Byeon, Bo-geun Kim, Jae-woo Park
Abstract: A user system is provided including a plurality of flash memory devices and a memory controller connected to the flash memory devices through a plurality of channels. The memory controller includes a voltage regulator configured to supply a power of the flash memory devices and a compensation unit configured to supply an additional power to the flash memory devices when a power required by the flash memory devices exceeds a predetermined level. The compensation unit includes a resistor unit connected to an output terminal of the voltage regulator and input terminals of the flash memory devices and a charging unit connected to input terminals of the flash memory devices. The charging unit is configured to supply an additional power to the flash memory devices according to voltages of input terminals of the flash memory devices.
Type:
Grant
Filed:
October 31, 2013
Date of Patent:
December 30, 2014
Assignee:
Samsung Electronics Co., Ltd.
Inventors:
In Bo Shim, Cheol Kwon, Iksung Park, Jong-Wook Jeong
Abstract: A semiconductor memory device includes a memory array including a plurality of memory cells, and a peripheral circuit configured to perform an erase operation by supplying a first erase voltage to selected memory cells and perform an erase verify operation by supplying an erase verify voltage to the selected memory cells, wherein the peripheral circuit is configured to increase the first erase voltage to a first level at a first rising rate for a first rising period and increase the first erase voltage to a first target level at a second rising rate lower than the first rising rate for a second rising period.
Abstract: A next read threshold is determined by determining a first number of solid state storage cells having a stored voltage which falls into a first voltage range and determining a second number of solid state storage cells having a stored voltage which falls into a second voltage range. A gradient is determine by taking a difference between the first number of solid state storage cells and the second number of solid state storage cells. The next read threshold is determined based at least in part on the gradient.
Type:
Grant
Filed:
July 5, 2013
Date of Patent:
December 30, 2014
Assignee:
SK hynix memory solutions inc.
Inventors:
Frederick K. H. Lee, Jason Bellorado, Arunkumar Subramanian, Lingqi Zeng, Xiangyu Tang, Ameen Aslam
Abstract: An instruction to write to a location in the Flash memory is received. It is determining if the Flash memory exposes a level placement setting associated with defining what voltage range corresponds to what level. In the event it is determined that the Flash memory exposes a level placement setting, an accurate coarse write is performed on the location, including by configuring the level placement setting to be a first value, and after the accurate coarse write is performed on the location, a fine write is performed on the location, including by configuring the level placement setting to be a second value, in response to receiving the instruction.
Abstract: Some embodiments include a memory device and a method of programming memory cells of the memory device. One such method can include applying a signal to a line associated with a memory cell, the signal being generated based on digital information. The method can also include, while the signal is applied to the line, determining whether a state of the memory cell is near a target state when the digital information has a first value, and determining whether the state of the memory cell has reached the target state when the digital information has a second value. Other embodiments including additional memory devices and methods are described.
Type:
Grant
Filed:
March 25, 2011
Date of Patent:
December 23, 2014
Assignee:
Micron Technology, Inc.
Inventors:
Violante Moschiano, Giovanni Santin, Michele Incarnati
Abstract: A novel NVM-based 2T or 2nT NAND-cell for a NAND-array for PLD, PAL and matching functions is disclosed. The preferable NVM cell can be ROM or Flash. The 2T flash cell preferably uses FN for both program and erase operation, while 2T ROM cell preferably to use phosphorus for ROM code implant to get negative Vt0.
Abstract: Word line switch transistors in a well in a substrate may be back biased. A memory array having non-volatile storage devices may be in a separate well in the substrate. The well of the word line switch transistors may be biased separately from the well of the non-volatile storage devices. Word line switch transistors may be back-biased during an erase operation. A first voltage may be applied to a first terminal of word line switch transistors that are coupled to blocks selected for erase. The first voltage may be applied to a first terminal of word line switch transistors that are coupled to blocks that are not selected for erase. The first voltage is passed to word lines in selected blocks, but is not passed to word lines in unselected blocks.
Abstract: A non-volatile semiconductor memory device according to embodiments has a memory cell array and a reading circuit, and, in a reading sequence, the reading circuit executes a prereading operation of supplying a first reading voltage to an adjacent word line and supplying a first reading pass voltage to a selected word line, and after executing the prereading operation, executes a main reading operation of supplying a fixed second reading voltage to the selected word line and supplying a fixed second reading pass voltage to the adjacent word line while sensing a plurality of electrical physical amounts of a target memory cell with different reading conditions.
Type:
Grant
Filed:
June 29, 2012
Date of Patent:
December 23, 2014
Assignee:
Kabushiki Kaisha Toshiba
Inventors:
Toshiaki Edahiro, Masahiro Noguchi, Koki Ueno
Abstract: A control circuit for a nonvolatile semiconductor storage device, during a write operation, configures multiple bit lines so that bit lines that are adjacent to select bit lines are nonselect bit lines. The control circuit applies a first voltage to a write bit line that is included in the select bit lines, and also applies a second voltage that is higher than the first voltage, to a write inhibit bit line that is included in the select bit lines. Then, the control circuit applies a third voltage that is higher than the second voltage to the nonselect bit lines. As a result, the control circuit raises the voltage of the write inhibit bit line, while maintaining the write bit line at the first voltage. Next, the control circuit applies a fourth voltage for the write operation to the drain-side select gate line.
Abstract: There is disclosed an operating method of a semiconductor device including programming a memory cell by supplying a program voltage to a control gate of the memory cell and a detrap voltage to a well which is formed in a semiconductor substrate, and subsequently removing electrons trapped in a tunnel insulating layer of the memory cell by supplying a voltage lower than the detrap voltage to the control gate while also supplying the detrap voltage to the well before the programmed memory cell is verified.
Abstract: A non-volatile semiconductor storage device includes: a memory cell array having memory cells arranged therein, the memory cells storing data in a non-volatile manner; and a plurality of transfer transistors transferring a voltage to the memory cells, the voltage to be supplied for data read, write and erase operations with respect to the memory cells. Each of the transfer transistors includes: a gate electrode formed on a semiconductor substrate via a gate insulation film; and diffusion layers formed to sandwich the gate electrode therebetween and functioning as drain/source layers. Upper layer wirings are provided above the diffusion layers and provided with a predetermined voltage to prevent depletion of the diffusion layers at least when the transfer transistors become conductive.
Type:
Grant
Filed:
March 21, 2013
Date of Patent:
December 30, 2014
Assignee:
Kabushiki Kaisha Toshiba
Inventors:
Dai Nakamura, Hiroyuki Kutsukake, Kenji Gomikawa, Takeshi Shimane, Mitsuhiro Noguchi, Koji Hosono, Masaru Koyanagi, Takashi Aoi